1. Field of the Invention
The present invention relates to an energy management device. More particularly, the present invention relates to an energy management device useful, inter alia, as a vehicular bumper.
2. Description of the Prior Art
Energy management devices (also known as energy absorbing devices) are known. Such devices can take one of a variety of shapes and forms. Currently, one of the major applications for energy absorbing panels is in use in vehicles, particularly automobiles. Such panels, when used in vehicles, would be of great convenience if they could be included in or substituted for a conventional vehicular bumper.
Conventionally, vehicular bumpers have been constructed with a fascia covering a rigid beam which was connected to the vehicle by two or more suitable rails. During the evolution of vehicular bumpers, it has become conventional to improve energy absorption of the bumper by the use a hydraulic rails. It is also known to construct vehicular bumpers to include one or more fluid containing bladders to improve the energy absorbing capability of the bumper.
As early as the 1960's, it was known to employ a foam energy absorber to cover the rigid beam. The original foam energy absorber included a rigid, high density polyurethane foam. As improvements in vehicular fuel efficiency became desirable, the foam energy absorber was replaced with relatively low density expanded polypropylene foam. Vehicular bumpers comprising foam energy absorbers constructed of semi-rigid, relatively low density expanded polypropylene foam are currently in commercial production.
As is known in the art, most jurisdictions require that vehicular bumpers meet and pass a variety of tests. While the precise tests are jurisdiction-specific, the requirement of having the bumper meet and pass the tests is virtually universal. In the United States all vehicular bumpers are required to meet and pass the standard prescribed by 49 C.F.R. Part 581, including the Preamble to Part 581 (Pre 1-56, inclusive), the contents of which are hereby incorporated by reference. This standard, inter alia, serves to limit damage to vehicular bumpers and other vehicle surfaces in low-speed crashes and impacts.
The art is continually in need of energy management devices useful, for example, in vehicular bumpers, which meet and pass the standard set out in 49 C.F.R. Part 581, and possess improved energy absorbing properties. Enhanced energy management properties of the bumper may be useful in effecting the crash pulse of the vehicle and reducing the forces impacting the occupant interior compartment. Such energy management devices have the potential to contribute to satisfying the European Frontal Impact Test (Off-Set) relating to Directive 96/79/EC of the European Parliament and of the Council of Dec. 16, 1996, the contents of which are hereby incorporated by reference. The European Frontal Impact Test, which requires 56 kph vehicular impact into a deformable barrier off-set by 40% is being implemented for the purposes of occupant protection.